Steve Klabnik
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Arguing about arguments
Here’s some Rust code: // define a function fn foo (x : i32 , y : i32 ) -> i32 { // body elided } // call it let z = foo ( 5 , 6 ); In programming language jargon, we call x and y parameters and 5 and 6 arguments . Rust does not have many fancy features related to parameters and…
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So, what happened to my Claude Code series?
I started off this year writing a lot, and wanted to keep up the pace. I did good at first! And then… I didn’t manage to. In some ways, this is because I have just been super busy! I’ve never had less free time, and I’m okay with that. There’s a tremendous amount of good things…
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Too many words about DIDs
Your “Bluesky account” is not just a Bluesky account: it is an account that can be used with a variety of other applications. This post is going to be an exploration of part of what that means from a technical perspective, so if you’re not a software developer, this post isn’t…
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Compilers and AI 'cyber' defense
I haven’t had time to blog in a while, I have a lot to say, but have been doing a lot of things and so haven’t gotten words down in a while. One of those things in the past few weeks has been picking back up my Rue project. I’m really excited for what it’s turning into, even…
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The most important thing when working with LLMs
Okay, so you’ve got the basics of working with Claude going. But you’ve probably run into some problems: Claude doesn’t do what you want it to do, it gets confused about what’s happening and goes off the rails, all sorts of things can go wrong. Let’s talk about how to improve…
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Agentic development basics
In my last post, I suggested that you should start using Claude in your software development process via read-only means at first. The idea is just to get used to interacting with the AI, seeing what it can do, and seeing what it struggles with. Once you’ve got a handle on that…
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How to think about Gas Town
I want to continue with my series on how you can use Claude Code for software development , but I have at least two posts I need to write first. This post is one of those two. Thanks for all of the kind words you all have said about the first post in the series, I’ll absolutely…
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Getting started with Claude for software development
2025 was an interesting year in many ways. One way in which it was interesting for me is that I went from an AI hater to a pretty big user. And so I’ve had a few requests for a “using Claude” guide, so I figure new year, why not give it a shot? The lack of this kind of content…
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Thirteen years of Rust and the birth of Rue
I started using Rust on December 21, 2012. It’s now December 22, 2025. That’s a long time. I don’t have a ton of thoughts about Rust to share today, like I thought I might. I program in the language regularly, it’s nice, I prefer it to all others. I have my beefs and my regrets,…
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I see a future in jj
In December of 2012, I was home for Christmas, reading Hacker News. And that’s when I saw “ Rust 0.5 released ."" I’m a big fan of programming languages, so I decided to check it out. At the time, I was working on Ruby and Rails, but in college, I had wanted to focus on…
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A tale of two Claudes
It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of…
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Is Rust faster than C?
Someone on Reddit recently asked: What would make a Rust implementation of something faster than a C implementation, all things being the same? I think this is a great and interesting question! It’s really tough because it ultimately relies on what exactly you mean by “all things…
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I am disappointed in the AI discourse
Recently, something happened that made me kind of like, break a little bit. I’m still not entirely sure why this whole thing bothers me so much, but here’s a blog post about it. I happened to ask ChatGPT something for fun. I often do this just to see what it says, and if I feel…
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Rust 1.0, ten years later
It’s kind of hard to believe it’s been ten years since Rust 1.0 was released. I stopped working on Rust three years ago, and frankly, the last three years have been pretty rough. But 2025 is shaping up to be a really good year for me, with lots of positive changes. With that in…
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Thoughts on Bluesky Verification
Today, Bluesky rolled out blue checks . And, I was given one. Now, I’m not the biggest fan of this sort of feature, however, I also don’t really think this kind of feature is for me. I really like the idea of domain verification; I have been like “oh okay that’s coming from a…
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Thinking like a compiler: places and values in Rust
A while back, someone on the internet asked about this syntax in Rust: * pointer_of_some_kind = blah; They wanted to know how the compiler understands this code, especially if the pointer wasn’t a reference, but a smart pointer. I wrote them a lengthy reply, but wanted to expand…
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Does unsafe undermine Rust's guarantees?
When people first hear about unsafe in Rust, they often have questions. A very normal thing to ask is, “wait a minute, doesn’t this defeat the purpose?” And while it’s a perfectly reasonable question, the answer is both straightforward and has a lot of nuance. So let’s talk about…
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Choosing Languages
I tried to write this post yesterday, but I didn’t like my approach there. Last night, I had a conversation with one of my best friends about it, and he encouraged me to write this, but in a different way. I think this way is better, so thanks, dude. The other day, Microsoft…
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A Happy Day for Rust
A while back, I wrote A sad day for Rust about the Actix-web unsafe controversy. The short of it was, Actix-web was using some unsound unsafe code. When this was discovered, people responded pretty harshly, and the maintainer quit. Others picked up the work, but it still wasn’t…
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When should I use String vs &str?
Rust has two main string types: String and &str . Sometimes, people argue that these two types make Rust code difficult to write, because you have to think about which one you should be using in a given situation. My experience of writing Rust is that I don’t really think about…
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